ABSTRACT The widespread adoption of electronic health records (EHR) systems is changing how healthcare professionals (HCPs) deliver care and communicate with each other. Although evidence suggests that EHR use was associated with increased adherence to guidelines, enhanced clinical surveillance, and decreased medication errors, the impact of EHR use on communication and teamwork among HCPs is not well understood. A major challenge is that most care teams are virtual teams that are difficult to study or improve their practice using traditional methods. The objective of this project is to develop methods for measuring EHR communication networks, defined as EHR-based information sharing connections among HCPs, in virtual care teams and examine the relationship between EHR communication networks and care quality. We will address two specific aims. The first aim is to develop and compare methods for measuring EHR communication networks in virtual care teams for breast, colorectal, and non-small cell lung cancer patients. We will extract data from the Virginia Commonwealth University Health System's EHR system to construct EHR communication networks among HCPs who provide care to a patient between the time of diagnosis and completion of the first-course treatment. We will use three methods for constructing the temporal EHR communication networks: the weighted and directed network, the exponential-threshold network, and the multivariate marked Hawkes process. We will compare networks constructed from different methods. The second aim is to examine associations between EHR communication network structures and patient outcomes, including 30-day re-admissions and emergency department (ED) visits, one-year utilization of inpatient and ED services, and one-year mortality. We will apply appropriate statistical techniques (generalized linear mixed models) to analyze associations between communication network structures and subsequent patient outcomes, adjusted for patient characteristics and comorbidities. We expect that this project will build a foundation for future research and quality improvement efforts to unleash the enormous potential of using EHR data to understand complex communication activities in virtual care teams and design team-based interventions, leading to accelerated progress towards improving care quality and outcomes through the use of health information technology.